Examples of current wireless communications systems are Code Division Multiple Access (CDMA) networks, such as those compliant with existing and evolving 3GPP and 3GPP2 specifications, TD-CDMA, TD-SCDMA, WiMAX (i.e., IEEE §802.16) and IEEE §802.20 compliant networks. CDMA technology, for example, allows multiple cellular phone users to share the same frequency spectrum, and uses a code spread carrier with a different and essentially orthogonal instance of the spreading code assigned to each mobile unit within a cell. The base station receiver in a CDMA station correlates the received signal from a mobile unit with the desired de-spreading code, extracting the transmitted digital signal with a sufficient signal-to-noise ratio to achieve a satisfactory data error rate.
Filters are commonly used to remove unwanted noise from signals. One of limitations of filters in the past has been the need to configure filters for specific applications and receive bands. A high quality filter which can be electronically re-configured for MultiBand operation without the need to manually adjust or to change the physical filters is desirable.